A railroad includes a pair of parallel metal rails interconnected and held in place by a plurality of crossties, also called railroad ties or ties, along a path of rocks or ballast. The rails are interconnected and held in place on the ties by positioning railroad tie plates between the rails and the ties. Railroad tie plates increase the load bearing surface area on the tie for a load on the rail generated by rail supported vehicles, typically train engines and train cars. The load on the rail is transferred from the rail to the tie through the railroad tie plate. In the past, metal railroad spikes were used to hold both the railroad tie plates and the rails in position on the ties. Today, spikes or lag bolts can be used to attach the railroad tie plate to the tie while the rail is attached to the tie plate using a fastener, such as a clip.
Historically, railroads were built using hand tools and manual labor. The equipment first used in the railroad construction industry was for clearing and preparing railway beds. Later, purpose built, custom built, or specialty equipment specifically designed for railroad construction was developed and used to construct railroads. Currently, the steps involved in building a railroad, including the setting of ties, laying of rail, grading of ballast, and driving spikes, is all done by railroad construction equipment specifically designed for such tasks. There is also railroad construction equipment that can effect repairs, such as tie replacement equipment that removes a tie from under the rails of an existing railroad track and then inserts a new tie, which is later spiked to a tie plate attached to the rails.
Purpose built railroad construction equipment is typically supported by other material handling equipment. For example, front-end loaders and dump trucks preposition ballast for railway ballast grading equipment. In another example, excavators with mechanical claws preposition ties for railway tie setting equipment. Regardless of the equipment custom built to build railroads, manual labor is still used to preposition railway tie plates for railway tie plate installation equipment. That is, manual labor is done to specifically position a pair of railway tie plates near, on, or between the rails so that railway tie plate installation equipment can later acquire the railway tie plates and install the railway tie plates between the ties and the rails.